TY - JOUR A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Wochatz, Monique A1 - Kopinski, Stephan A1 - Sonnenburg, Dominik A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Mayer, Frank T1 - Feasability of An Eccentric Isokinetic Protocol to Induce Trunk Muscle Damage: A Pilot Study JF - Sports Medicine International Open N2 - Eccentric exercise is discussed as a treatment option for clinical populations, but specific responses in terms of muscle damage and systemic inflammation after repeated loading of large muscle groups have not been conclusively characterized. Therefore, this study tested the feasibility of an isokinetic protocol for repeated maximum eccentric loading of the trunk muscles. Nine asymptomatic participants (5 f/4 m; 34±6 yrs; 175±13 cm; 76±17 kg) performed three isokinetic 2-minute all-out trunk strength tests (1x concentric (CON), 2x eccentric (ECC1, ECC2), 2 weeks apart; flexion/extension, 60°/s, ROM 55°). Outcomes were peak torque, torque decline, total work, and indicators of muscle damage and inflammation (over 168 h). Statistics were done using the Friedman test (Dunn’s post-test). For ECC1 and ECC2, peak torque and total work were increased and torque decline reduced compared to CON. Repeated ECC bouts yielded unaltered torque and work outcomes. Muscle damage markers were highest after ECC1 (soreness 48 h, creatine kinase 72 h; p<0.05). Their overall responses (area under the curve) were abolished post-ECC2 compared to post-ECC1 (p<0.05). Interleukin-6 was higher post-ECC1 than CON, and attenuated post-ECC2 (p>0.05). Interleukin-10 and tumor necrosis factor-α were not detectable. All markers showed high inter-individual variability. The protocol was feasible to induce muscle damage indicators after exercising a large muscle group, but the pilot results indicated only weak systemic inflammatory responses in asymptomatic adults. KW - exercise KW - eccentric KW - muscle fatigue KW - trunk muscles KW - isokinetics KW - repeated bout effect KW - inflammation KW - exercise induced muscle damage KW - interleukin-6 KW - internleukin-10 KW - tumor necrosis factor-α Y1 - 2021 U6 - https://doi.org/10.1055/a-1757-6724 SN - 2367-1890 VL - 6 SP - E9 EP - E17 PB - Thieme CY - Stuttgart ET - 1 ER - TY - CHAP A1 - Wochatz, Monique A1 - Kopinski, Stephan A1 - Engel, Tilman A1 - Müller, Steffen A1 - Mayer, Frank T1 - Flexion-extension ratio of trunk peak torque measures and antagonistic activity in males and females T2 - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine Y1 - 2014 SN - 0195-9131 SN - 1530-0315 VL - 46 IS - 5 SP - 148 EP - 148 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - THES A1 - Wochatz, Monique T1 - Influence of different loading conditions on scapular movement and scapular muscle activation patterns T1 - Der Einfluss verschiedener Lastsituationen auf Bewegungs- und Aktivitätsmuster des Schulterblatts N2 - The scapula plays a significant role in efficient shoulder movement. Thus, alterations from typical scapular motion during upper limb movements are thought to be associated with shoulder pathologies. However, a clear understanding of the relationship is not yet obtained.. Scapular alterations may only represent physiological variability as their occurrence can appear equally as frequent in individuals with and without shoulder disorders. Evaluation of scapular motion during increased load might be a beneficial approach to detect clinically relevant alterations. However, functional motion adaptations in response to maximum effort upper extremity loading has not been established yet. Therefore, the overall purpose of this research project was to give further insight in physiological adaptations of scapular kinematics and their underlying scapular muscle activity in response to high demanding shoulder movements in healthy asymptomatic individuals. Prior to the investigation of the effect of various load situation, the reproducibility of scapular kinematics and scapular muscle activity were evaluated under maximum effort arm movements. Healthy asymptomatic adults performed unloaded and maximal loaded concentric and eccentric isokinetic shoulder flexion and extension movements in the scapular plane while scapular kinematics and scapular muscle activity were simultaneously assessed. A 3D motion capture system (infra-red cameras & reflective markers) was utilized to track scapular and humerus motion in relation to the thorax. 3D scapular position angles were given for arm raising and lowering between humerus positions of 20° and 120° flexion. To further characterize the scapular pattern, the scapular motion extent and scapulohumeral rhythm (ratio of scapular and humerus motion extent) were determined. Muscle activity of the upper and lower trapezius and the serratus anterior were assessed with surface electromyography. Amplitudes were calculated for the whole ROM and four equidistant movement phases. Reliability was characterized by overall moderate to good reproducibility across the load conditions. Irrespective of applied load, scapular kinematics followed a motion pattern of continuous upward rotation, posterior tilt and external rotation during arm elevation and a continuous downward rotation, anterior tilt and internal rotation during arm lowering. However, kinematics were altered between maximal loaded and unloaded conditions showing increased upward rotation, reduced posterior tilt and external rotation. Further, the scapulohumeral rhythm was decreased and scapular motion extent increased under maximal loaded movements. Muscle activity during maximum effort were of greater magnitude and differed in their pattern in comparison to the continuous increase and decrease of activity during unloaded shoulder flexion and extension. Relationships between scapular kinematics and their underlying scapular muscle activity could only be identified for a few isolated combinations, whereas the majority showed no associations. Scapular kinematics and scapular muscle activity pattern alter according to the applied load. Alterations between the load conditions comply in magnitude and partially in direction with differences seen between symptomatic and asymptomatic individuals. Even though long-term effects of identified adaptations in response to maximum load are so far unclear, deviations from typical scapular motion or muscle activation should not per se be seen as indicators of shoulder impairment. However, evaluation of alterations in scapular motion and activation in response to maximum effort may have the potential to identify individuals that are unable to cope with increased upper limb demands. Findings further challenge the understanding of scapular motion and stabilization by the trapezius and serratus anterior muscles, as clear relationships between the underlying scapular muscle activity and scapular kinematics were neither observed during unloaded nor maximal loaded shoulder movements. N2 - Das Schulterblatt ist entscheidend für die uneingeschränkte Bewegung und Positionierung der oberen Extremität. Atypische Bewegungsmuster des Schulterblatts werden deshalb oft mit Schulterpathologien in Verbindung gebracht, obwohl die zugrundeliegenden Mechanismen noch nicht ausreichend geklärt sind. Abweichungen stellen möglicherweise nur eine Form physiologischer Variabilität dar, da Veränderungen der Schulterblattbewegung sowohl bei Personen mit als auch ohne Schulterbeschwerden auftreten können. Die Beurteilung der Schulterblattbewegung unter erhöhten Lastbedingungen könnte hilfreich bei der Differenzierung von funktionellen und klinisch relevanten Veränderungen sein. Jedoch sind physiologische Anpassungen der Schulterblattkinematik in Reaktion auf maximale Anforderungen während einer Bewegungsaufgabe der oberen Extremität bisher nicht untersucht. Das Ziel dieses Forschungsprojektes war es deshalb weitere Erkenntnisse hinsichtlich physiologischer Anpassungen der Schulterblattkinematik und ihrer zugrundeliegenden Muskelaktivität zu erlangen. Bevor die Effekte verschiedener Belastungssituationen untersucht wurden, erfolgte die Beurteilung der Reproduzierbarkeit der Schulterblattkinematik sowie der Aktivitätslevel schulterblattstabilisierender Muskeln unter maximaler Anstrengung. Gesunde asymptomatische Erwachsene führten isokinetische Schulterbewegungen in Flexion und Extension unter unbelasteten sowie maximal belasteten Bedingungen durch. Zeitgleich wurde die Schulterblattkinematik sowie die Aktivität schulterstabilisierender Muskeln erfasst. Mit Hilfe eines 3D Kamera Systems (Infrarotkameras & reflektierende Marker) wurden Winkelpositionen des Schulterblatts für Humerus-Positionen zwischen 20° und 120° Flexion bestimmt. Zur weiteren Charakterisierung der Schulterblattbewegung wurde das Ausmaß der Schulterblattrotation sowie der skapulohumerale Rhythmus (Verhältnis von Schulterblatt- und Humerus-Bewegung) ermittelt. Während der Schulterbewegungen wurde die Muskelaktivität des oberen und unteren Trapezius sowie des Serratus anterior mit Oberflächen-Elektromyographie erfasst. Aktivitätslevel wurden für das gesamte Bewegungsausmaß sowie für einzelne Bewegungsphasen berechnet. Eine moderate bis gute Reproduzierbarkeit der Winkelpositionen des Schulterblatts sowie der Aktivitätslevel der schulterblattstabilisierenden Muskulatur konnte unter den verschiedenen Lastbedingungen erreicht werden. Unabhängig von der applizierten Last folgte das Schulterblatt einer kontinuierlichen Aufwärtsrotation, Rückwärtsneigung und Außenrotation während der Schulterflexion und einer kontinuierlichen Abwärtsrotation, Vorwärtsneigung und Innenrotation während der Schulterextension. Bei maximalen Belastungen zeigte das Schulterblatt jedoch eine gesteigerte Aufwärtsrotation sowie eine verringerte Rückwärtsneigung und Außenrotation im Vergleich zur unbelasteten Schulterbewegung. Der skapulohumerale Rhythmus verringerte sich und auch das Ausmaß der Schulterblattrotation war unter maximaler Last erhöht. Die Muskelaktivität zeigte sich unter maximaler Anstrengung nicht nur im Ausmaß gesteigert sondern wies auch ein verändertes Aktivitätsmuster im Verlauf der Bewegungen im Vergleich zur kontinuierlichen Zu- und Abnahme der Aktivität während unbelasteter Bedingungen auf. Korrelationen zwischen dem Ausmaß der Schulterblattrotation und dem Aktivitätslevel der Schulterblattmuskulatur konnten nur für einige wenige isolierte Kombinationen identifiziert werden, während die Mehrheit keine Assoziationen zeigte. Die Kinematik des Schulterblatts und die Aktivitätsmuster der Schulterblattmuskulatur ändern sich in Abhängigkeit der Belastung. Veränderungen der Kinematik und Aktivitätsmuster entsprechen dabei im Ausmaß und teilweise in der Ausrichtung den bekannten Unterschieden zwischen symptomatischen und asymptomatischen Populationen. Obwohl die langfristigen Auswirkungen dieser veränderten Schulterblattkinematik unter maximalen Belastungen bislang unklar sind, sollten Abweichungen von der typischen Bewegung des Schulterblatts sowie bekannter Aktivitätsmuster per se nicht als Indikatoren für eine Beeinträchtigung der Schulterfunktion angesehen werden. Dennoch könnten Untersuchungen der Schulterblattkinematik sowie der Aktivität schulterblattrotierender und –stabilisierender Muskeln unter erhöhten Anforderungen Personen identifizieren die aufgrund mangelnder Anpassung die gesteigerten Lasten nicht kompensieren können. Ein klares Zusammenspiel von Schulterblattkinematik und rotierender sowie stabilisierender Schulterblattmuskulatur ließ sich weder unter unbelasteten noch maximal belasteten Bedingungen aufzeigen. KW - scapular kinematics KW - 3D motion analysis KW - scapular muscles KW - electromyography KW - Schulterblattkinematik KW - 3D-Bewegungsanalyse KW - Schulterblattmuskulatur KW - Elektromyografie Y1 - 2021 ER - TY - JOUR A1 - Schomöller, Anne A1 - Risch, Lucie A1 - Kaplick, Hannes A1 - Wochatz, Monique A1 - Engel, Tilman A1 - Schraplau, Anne A1 - Sonnenburg, Dominik A1 - Huppertz, Alexander A1 - Mayer, Frank T1 - Inter-rater and inter-session reliability of lumbar paraspinal muscle composition in a mobile MRI device JF - BJR : an international journal of radiology, radiation oncology and all related sciences / British Institute of Radiology N2 - Objective: To assess the reliability of measurements of paraspinal muscle transverse relaxation times (T2 times) between two observers and within one observer on different time points.
Methods: 14 participants (9f/5m, 33 +/- 5 years, 176 +/- 10 cm, 73 +/- 12 kg) underwent 2 consecutive MRI scans (M1,M2) on the same day, followed by 1 MRI scan 13-14 days later (M3) in a mobile 1.5 Tesla MRI. T2 times were calculated in T-2 weighted turbo spin- echo-sequences at the spinal level of the third lumbar vertebrae (11 slices, 2 mm slice thickness, 1 mm interslice gap, echo times: 20, 40, 60, 80, 100 ms) for M. erector spinae (ES) and M. multifidius (MF). The following reliability parameter were calculated for the agreement of T2 times between two different investigators (OBS1 & OBS2) on the same MRI (inter rater reliability, IR) and by one investigator between different MRI of the same participant (intersession variability, IS): Test-Retest Variability (TRV, Differences/Mean*100); Coefficient of Variation (CV, Standard deviation/Mean*100); Bland-Altman Analysis (systematic bias = Mean of the Differences; Upper/Lower Limits of Agreement = Bias+/-1.96*SD); Intraclass Correlation Coefficient 3.1 (ICC) with absolute agreement, as well as its 95% confidence interval.
Results: Mean TRV for IR was 2.6% for ES and 4.2% for MF. Mean TRV for IS was 3.5% (ES) and 5.1% (MF). Mean CV for IR was 1.9 (ES) and 3.0 (MF). Mean CV for IS was 2.5% (ES) and 3.6% (MF). A systematic bias of 1.3 ms (ES) and 2.1 ms (MF) were detected for IR and a systematic bias of 0.4 ms (ES) and 0.07 ms (MF) for IS. ICC for IR was 0.94 (ES) and 0.87 (MF). ICC for IS was 0.88 (ES) and 0.82 (MF).
Conclusion: Reliable assessment of paraspinal muscle T2 time justifies its use for scientific purposes. The applied technique could be recommended to use for future studies that aim to assess changes of T2 times, e.g. after an intense bout of eccentric exercises. Y1 - 2021 U6 - https://doi.org/10.1259/bjr.20210141 SN - 0007-1285 SN - 1748-880X VL - 94 IS - 1127 PB - Wiley CY - Bognor Regis ER - TY - CHAP A1 - Wochatz, Monique A1 - Cassel, Michael A1 - König, Niklas A1 - Fröhlich, Katja A1 - Mayer, Frank T1 - Intra- and inter-observer variability of a retrospective analysis of achilles tendon ultrasound scans T2 - Medicine and science in sports and exercise : official journal of the American College of Sports Medicine Y1 - 2013 SN - 0195-9131 SN - 1530-0315 VL - 45 IS - 5 SP - 239 EP - 239 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Wochatz, Monique A1 - Rabe, Sophie A1 - Wolter, Martin A1 - Engel, Tilman A1 - Mueller, Steffen A1 - Mayer, Frank T1 - Muscle activity of upper and lower trapezius and serratus anterior during unloaded and maximal loaded shoulder flexion and extension JF - International Biomechanics N2 - Altered scapular muscle activity is mostly described under unloaded and submaximal loaded conditions in impingement patients. However, there is no clear evidence on muscle activity with respect to movement phases under maximum load in healthy subjects. Therefore, this study aimed to investigate scapular muscle activity under unloaded and maximum loaded isokinetic shoulder flexion and extension in regard to the movement phase. Fourteen adults performed unloaded (continuous passive motion [CPM]) as well as maximum loaded (concentric [CON], eccentric [ECC]) isokinetic shoulder flexion (Flex) and extension (Ext). Simultaneously, scapular muscle activity was measured by EMG. Root mean square was calculated for the whole ROM and four movement phases. Data were analyzed descriptively and by two-way repeated measures ANOVA. CPMFlex resulted in a linear increase of muscle activity for all muscles. Muscle activity during CONFlex and ECCFlex resulted in either constant activity levels or in an initial increase followed by a plateau in the second half of movement. CPMExt decreased with the progression of movement, whereas CONExt and ECCExt initially decreased and either levelled off or increased in the second half of movement. Scapular muscle activity of unloaded shoulder flexion and extension changed under maximum load showing increased activity levels and an altered pattern over the course of movement. KW - shoulder KW - scapular muscle activity KW - isokinetic testing KW - electromyography Y1 - 2017 U6 - https://doi.org/https://doi.org/10.1080/23335432.2017.1364668 VL - 4 IS - 2 SP - 68 EP - 76 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wochatz, Monique A1 - Tilgner, Nina A1 - Mueller, Steffen A1 - Rabe, Sophie A1 - Eichler, Sarah A1 - John, Michael A1 - Völler, Heinz A1 - Mayer, Frank T1 - Reliability and validity of the Kinect V2 for the assessment of lower extremity rehabilitation exercises JF - Gait & posture N2 - Research question: The purpose of this study was to evaluate the test-retest reliability of lower extremity kinematics during squat, hip abduction and lunge exercises captured by the Kinect and to evaluate the agreement to a reference 3D camera-based motion system. Methods: Twenty-one healthy individuals performed five repetitions of each lower limb exercise on two different days. Movements were simultaneously assessed by the Kinect and the reference 3D motion system. Joint angles and positions of the lower limb were calculated for sagittal and frontal plane. For the inter-session reliability and the agreement between the two systems standard error of measurement (SEM), bias with limits of agreement (LoA) and Pearson Correlation Coefficient (r) were calculated. Results: Parameters indicated varying reliability for the assessed joint angles and positions and decreasing reliability with increasing task complexity. Across all exercises, measurement deviations were shown especially for small movement amplitudes. Variability was acceptable for joint angles and positions during the squat, partially acceptable during the hip abduction and predominately inacceptable during the lunge. The agreement between systems was characterized by systematic errors. Overestimations by the Kinect were apparent for hip flexion during the squat and hip abduction/adduction during the hip abduction exercise as well as for the knee positions during the lunge. Knee and hip flexion during hip abduction and lunge were underestimated by the Kinect. Significance: The Kinect system can reliably assess lower limb joint angles and positions during simple exercises. The validity of the system is however restricted. An application in the field of early orthopedic rehabilitation without further development of post-processing techniques seems so far limited. KW - Reproducibility KW - Agreement KW - Markerless motion capture system KW - Telerehabilitation Y1 - 2018 U6 - https://doi.org/10.1016/j.gaitpost.2019.03.020 SN - 0966-6362 SN - 1879-2219 VL - 70 SP - 330 EP - 335 PB - Elsevier CY - Clare ER - TY - JOUR A1 - Risch, Lucie A1 - Wochatz, Monique A1 - Messerschmidt, Janin A1 - Engel, Tilman A1 - Mayer, Frank A1 - Cassel, Michael T1 - Reliability of evaluating achilles tendon vascularization assessed with doppler ultrasound advanced dynamic flow JF - Journal of ultrasound in medicine N2 - The reliability of quantifying intratendinous vascularization by high-sensitivity Doppler ultrasound advanced dynamic flow has not been examined yet. Therefore, this study aimed to investigate the intraobserver and interobserver reliability of evaluating Achilles tendon vascularization by advanced dynamic flow using established scoring systems. Methods-Three investigators evaluated vascularization in 67 recordings in a test-retest design, applying the Ohberg score, a modified Ohberg score, and a counting score. Intraobserver and interobserver agreement for the Ohberg score and modified Ohberg score was analyzed by the Cohen kappa and Fleiss kappa coefficients (absolute), Kendall tau b coefficient, and Kendall coefficient of concordance (W; relative). The reliability of the counting score was analyzed by intraclass correlation coefficients (ICC) 2.1 and 3.1, the standard error of measurement (SEM), and Bland-Altman analysis (bias and limits of agreement [LoA]). Results-Intraobserver and interobserver agreement (absolute/relative) ranged from 0.61 to 0.87/0.87 to 0.95 and 0.11 to 0.66/0.76 to 0.89 for the Ohberg score and from 0.81 to 0.87/0.92 to 0.95 and 0.64 to 0.80/0.88 to 0.93 for the modified Ohberg score, respectively. The counting score revealed an intraobserver ICC of 0.94 to 0.97 (SEM, 1.0-1.5; bias, -1; and LoA, 3-4 vessels). The interobserver ICC for the counting score ranged from 0.91 to 0.98 (SEM, 1.0-1.9; bias, 0; and LoA, 3-5 vessels). Conclusions-The modified Ohberg score and counting score showed excellent reliability and seem convenient for research and clinical practice. The Ohberg score revealed decent intraobserver but unexpected low interobserver reliability and therefore cannot be recommended. KW - advanced dynamic flow KW - intratendinous blood flow KW - musculoskeletal KW - reliability KW - ultrasound Y1 - 2017 U6 - https://doi.org/10.1002/jum.14414 SN - 0278-4297 SN - 1550-9613 VL - 37 IS - 3 SP - 737 EP - 744 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Wochatz, Monique A1 - Rabe, Sophie A1 - Wolter, Martin A1 - Engel, Tilman A1 - Mueller, Steffen A1 - Mayer, Frank T1 - Reproducibility of scapular muscle activity in isokinetic shoulder flexion and extension JF - Journal of electromyography and kinesiology N2 - Repetitive overhead movements have been identified as a main risk factor to develop shoulder complaints with scapular muscle activity being altered. Reliable assessment of muscle activity is essential to differentiate between symptomatic and asymptomatic individuals. Therefore, the present study aimed to investigate the intra-and inter-session reliability of scapular muscle activity during maximal isokinetic shoulder flexion and extension. Eleven asymptomatic adults performed maximum effort isokinetic shoulder flexion and extension (concentric and eccentric at 60 degrees/s) in a test-retest design. Muscle activity of the upper and lower trapezius and serratus anterior was assessed by sEMG. Root Mean Square was calculated for whole ROM and single movement phases of absolute and normalized muscle activity. Absolute (Bland-Altman analysis (Bias, LoA), Minimal detectable change (MDC)) and relative reliability parameters (Intraclass correlation coefficient (ICC), coefficient of variation (CV)/test-retest variability (TRV)) were utilized for the evaluation of reproducibility. Intra-session reliability revealed ICCs between 0.56 and 0.98, averaged CVs of 18% and average MDCs of 81 mV. Inter-session reliability resulted in ICCs between 0.13 and 0.93, averaged TRVs of 21%, average MDCs of 15% and systematic and random error between -8 +/- 60% and 12 +/- 36%. Scapular muscle activity assessed in overhead movements can be measured reliably under maximum load conditions, though variability is dependent on the movement phase. Measurement variability does not exceed magnitudes of altered scapular muscle activities as reported in previous studies. Therefore, maximum load application is a promising approach for the evaluation of changes in scapular control related to pathologies. (C) 2017 Elsevier Ltd. All rights reserved. Y1 - 2017 U6 - https://doi.org/10.1016/j.jelekin.2017.04.006 SN - 1050-6411 SN - 1873-5711 VL - 34 SP - 86 EP - 92 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Wochatz, Monique A1 - Rabe, Sophie A1 - Engel, Tilman A1 - Müller, Steffen A1 - Mayer, Frank T1 - Scapular kinematics during unloaded and maximal loaded isokinetic concentric and eccentric shoulder flexion and extension movements JF - Journal of electromyography & kinesiology : official journal of the International Society of Electrophysiology and Kinesiology N2 - Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms. KW - Isokinetics KW - Motion analysis KW - Scapular dyskinesis KW - Scapulohumeral rhythm KW - Scapulothoracic Y1 - 2020 U6 - https://doi.org/10.1016/j.jelekin.2021.102517 SN - 1050-6411 SN - 1873-5711 VL - 57 PB - Elsevier CY - Amsterdam ER -